1 /*
2 * Remote Processor Framework
3 *
4 * Copyright(c) 2011 Texas Instruments, Inc.
5 * Copyright(c) 2011 Google, Inc.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * * Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * * Neither the name Texas Instruments nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
25 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
28 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
29 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
30 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
31 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
32 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33 */
34
35 #ifndef REMOTEPROC_H
36 #define REMOTEPROC_H
37
38 #include <linux/types.h>
39 #include <linux/mutex.h>
40 #include <linux/virtio.h>
41 #include <linux/completion.h>
42 #include <linux/idr.h>
43 #include <linux/of.h>
44
45 /**
46 * struct resource_table - firmware resource table header
47 * @ver: version number
48 * @num: number of resource entries
49 * @reserved: reserved (must be zero)
50 * @offset: array of offsets pointing at the various resource entries
51 *
52 * A resource table is essentially a list of system resources required
53 * by the remote processor. It may also include configuration entries.
54 * If needed, the remote processor firmware should contain this table
55 * as a dedicated ".resource_table" ELF section.
56 *
57 * Some resources entries are mere announcements, where the host is informed
58 * of specific remoteproc configuration. Other entries require the host to
59 * do something (e.g. allocate a system resource). Sometimes a negotiation
60 * is expected, where the firmware requests a resource, and once allocated,
61 * the host should provide back its details (e.g. address of an allocated
62 * memory region).
63 *
64 * The header of the resource table, as expressed by this structure,
65 * contains a version number (should we need to change this format in the
66 * future), the number of available resource entries, and their offsets
67 * in the table.
68 *
69 * Immediately following this header are the resource entries themselves,
70 * each of which begins with a resource entry header (as described below).
71 */
72 struct resource_table {
73 u32 ver;
74 u32 num;
75 u32 reserved[2];
76 u32 offset[0];
77 } __packed;
78
79 /**
80 * struct fw_rsc_hdr - firmware resource entry header
81 * @type: resource type
82 * @data: resource data
83 *
84 * Every resource entry begins with a 'struct fw_rsc_hdr' header providing
85 * its @type. The content of the entry itself will immediately follow
86 * this header, and it should be parsed according to the resource type.
87 */
88 struct fw_rsc_hdr {
89 u32 type;
90 u8 data[0];
91 } __packed;
92
93 /**
94 * enum fw_resource_type - types of resource entries
95 *
96 * @RSC_CARVEOUT: request for allocation of a physically contiguous
97 * memory region.
98 * @RSC_DEVMEM: request to iommu_map a memory-based peripheral.
99 * @RSC_TRACE: announces the availability of a trace buffer into which
100 * the remote processor will be writing logs.
101 * @RSC_VDEV: declare support for a virtio device, and serve as its
102 * virtio header.
103 * @RSC_LAST: just keep this one at the end of standard resources
104 * @RSC_VENDOR_START: start of the vendor specific resource types range
105 * @RSC_VENDOR_END: end of the vendor specific resource types range
106 *
107 * For more details regarding a specific resource type, please see its
108 * dedicated structure below.
109 *
110 * Please note that these values are used as indices to the rproc_handle_rsc
111 * lookup table, so please keep them sane. Moreover, @RSC_LAST is used to
112 * check the validity of an index before the lookup table is accessed, so
113 * please update it as needed.
114 */
115 enum fw_resource_type {
116 RSC_CARVEOUT = 0,
117 RSC_DEVMEM = 1,
118 RSC_TRACE = 2,
119 RSC_VDEV = 3,
120 RSC_LAST = 4,
121 RSC_VENDOR_START = 128,
122 RSC_VENDOR_END = 512,
123 };
124
125 #define FW_RSC_ADDR_ANY (-1)
126
127 /**
128 * struct fw_rsc_carveout - physically contiguous memory request
129 * @da: device address
130 * @pa: physical address
131 * @len: length (in bytes)
132 * @flags: iommu protection flags
133 * @reserved: reserved (must be zero)
134 * @name: human-readable name of the requested memory region
135 *
136 * This resource entry requests the host to allocate a physically contiguous
137 * memory region.
138 *
139 * These request entries should precede other firmware resource entries,
140 * as other entries might request placing other data objects inside
141 * these memory regions (e.g. data/code segments, trace resource entries, ...).
142 *
143 * Allocating memory this way helps utilizing the reserved physical memory
144 * (e.g. CMA) more efficiently, and also minimizes the number of TLB entries
145 * needed to map it (in case @rproc is using an IOMMU). Reducing the TLB
146 * pressure is important; it may have a substantial impact on performance.
147 *
148 * If the firmware is compiled with static addresses, then @da should specify
149 * the expected device address of this memory region. If @da is set to
150 * FW_RSC_ADDR_ANY, then the host will dynamically allocate it, and then
151 * overwrite @da with the dynamically allocated address.
152 *
153 * We will always use @da to negotiate the device addresses, even if it
154 * isn't using an iommu. In that case, though, it will obviously contain
155 * physical addresses.
156 *
157 * Some remote processors needs to know the allocated physical address
158 * even if they do use an iommu. This is needed, e.g., if they control
159 * hardware accelerators which access the physical memory directly (this
160 * is the case with OMAP4 for instance). In that case, the host will
161 * overwrite @pa with the dynamically allocated physical address.
162 * Generally we don't want to expose physical addresses if we don't have to
163 * (remote processors are generally _not_ trusted), so we might want to
164 * change this to happen _only_ when explicitly required by the hardware.
165 *
166 * @flags is used to provide IOMMU protection flags, and @name should
167 * (optionally) contain a human readable name of this carveout region
168 * (mainly for debugging purposes).
169 */
170 struct fw_rsc_carveout {
171 u32 da;
172 u32 pa;
173 u32 len;
174 u32 flags;
175 u32 reserved;
176 u8 name[32];
177 } __packed;
178
179 /**
180 * struct fw_rsc_devmem - iommu mapping request
181 * @da: device address
182 * @pa: physical address
183 * @len: length (in bytes)
184 * @flags: iommu protection flags
185 * @reserved: reserved (must be zero)
186 * @name: human-readable name of the requested region to be mapped
187 *
188 * This resource entry requests the host to iommu map a physically contiguous
189 * memory region. This is needed in case the remote processor requires
190 * access to certain memory-based peripherals; _never_ use it to access
191 * regular memory.
192 *
193 * This is obviously only needed if the remote processor is accessing memory
194 * via an iommu.
195 *
196 * @da should specify the required device address, @pa should specify
197 * the physical address we want to map, @len should specify the size of
198 * the mapping and @flags is the IOMMU protection flags. As always, @name may
199 * (optionally) contain a human readable name of this mapping (mainly for
200 * debugging purposes).
201 *
202 * Note: at this point we just "trust" those devmem entries to contain valid
203 * physical addresses, but this isn't safe and will be changed: eventually we
204 * want remoteproc implementations to provide us ranges of physical addresses
205 * the firmware is allowed to request, and not allow firmwares to request
206 * access to physical addresses that are outside those ranges.
207 */
208 struct fw_rsc_devmem {
209 u32 da;
210 u32 pa;
211 u32 len;
212 u32 flags;
213 u32 reserved;
214 u8 name[32];
215 } __packed;
216
217 /**
218 * struct fw_rsc_trace - trace buffer declaration
219 * @da: device address
220 * @len: length (in bytes)
221 * @reserved: reserved (must be zero)
222 * @name: human-readable name of the trace buffer
223 *
224 * This resource entry provides the host information about a trace buffer
225 * into which the remote processor will write log messages.
226 *
227 * @da specifies the device address of the buffer, @len specifies
228 * its size, and @name may contain a human readable name of the trace buffer.
229 *
230 * After booting the remote processor, the trace buffers are exposed to the
231 * user via debugfs entries (called trace0, trace1, etc..).
232 */
233 struct fw_rsc_trace {
234 u32 da;
235 u32 len;
236 u32 reserved;
237 u8 name[32];
238 } __packed;
239
240 /**
241 * struct fw_rsc_vdev_vring - vring descriptor entry
242 * @da: device address
243 * @align: the alignment between the consumer and producer parts of the vring
244 * @num: num of buffers supported by this vring (must be power of two)
245 * @notifyid is a unique rproc-wide notify index for this vring. This notify
246 * index is used when kicking a remote processor, to let it know that this
247 * vring is triggered.
248 * @pa: physical address
249 *
250 * This descriptor is not a resource entry by itself; it is part of the
251 * vdev resource type (see below).
252 *
253 * Note that @da should either contain the device address where
254 * the remote processor is expecting the vring, or indicate that
255 * dynamically allocation of the vring's device address is supported.
256 */
257 struct fw_rsc_vdev_vring {
258 u32 da;
259 u32 align;
260 u32 num;
261 u32 notifyid;
262 u32 pa;
263 } __packed;
264
265 /**
266 * struct fw_rsc_vdev - virtio device header
267 * @id: virtio device id (as in virtio_ids.h)
268 * @notifyid is a unique rproc-wide notify index for this vdev. This notify
269 * index is used when kicking a remote processor, to let it know that the
270 * status/features of this vdev have changes.
271 * @dfeatures specifies the virtio device features supported by the firmware
272 * @gfeatures is a place holder used by the host to write back the
273 * negotiated features that are supported by both sides.
274 * @config_len is the size of the virtio config space of this vdev. The config
275 * space lies in the resource table immediate after this vdev header.
276 * @status is a place holder where the host will indicate its virtio progress.
277 * @num_of_vrings indicates how many vrings are described in this vdev header
278 * @reserved: reserved (must be zero)
279 * @vring is an array of @num_of_vrings entries of 'struct fw_rsc_vdev_vring'.
280 *
281 * This resource is a virtio device header: it provides information about
282 * the vdev, and is then used by the host and its peer remote processors
283 * to negotiate and share certain virtio properties.
284 *
285 * By providing this resource entry, the firmware essentially asks remoteproc
286 * to statically allocate a vdev upon registration of the rproc (dynamic vdev
287 * allocation is not yet supported).
288 *
289 * Note: unlike virtualization systems, the term 'host' here means
290 * the Linux side which is running remoteproc to control the remote
291 * processors. We use the name 'gfeatures' to comply with virtio's terms,
292 * though there isn't really any virtualized guest OS here: it's the host
293 * which is responsible for negotiating the final features.
294 * Yeah, it's a bit confusing.
295 *
296 * Note: immediately following this structure is the virtio config space for
297 * this vdev (which is specific to the vdev; for more info, read the virtio
298 * spec). the size of the config space is specified by @config_len.
299 */
300 struct fw_rsc_vdev {
301 u32 id;
302 u32 notifyid;
303 u32 dfeatures;
304 u32 gfeatures;
305 u32 config_len;
306 u8 status;
307 u8 num_of_vrings;
308 u8 reserved[2];
309 struct fw_rsc_vdev_vring vring[0];
310 } __packed;
311
312 struct rproc;
313
314 /**
315 * struct rproc_mem_entry - memory entry descriptor
316 * @va: virtual address
317 * @dma: dma address
318 * @len: length, in bytes
319 * @da: device address
320 * @release: release associated memory
321 * @priv: associated data
322 * @name: associated memory region name (optional)
323 * @node: list node
324 * @rsc_offset: offset in resource table
325 * @flags: iommu protection flags
326 * @of_resm_idx: reserved memory phandle index
327 * @alloc: specific memory allocator function
328 */
329 struct rproc_mem_entry {
330 void *va;
331 dma_addr_t dma;
332 int len;
333 u32 da;
334 void *priv;
335 char name[32];
336 struct list_head node;
337 u32 rsc_offset;
338 u32 flags;
339 u32 of_resm_idx;
340 int (*alloc)(struct rproc *rproc, struct rproc_mem_entry *mem);
341 int (*release)(struct rproc *rproc, struct rproc_mem_entry *mem);
342 };
343
344 struct firmware;
345
346 /**
347 * enum rsc_handling_status - return status of rproc_ops handle_rsc hook
348 * @RSC_HANDLED: resource was handled
349 * @RSC_IGNORED: resource was ignored
350 */
351 enum rsc_handling_status {
352 RSC_HANDLED = 0,
353 RSC_IGNORED = 1,
354 };
355
356 /**
357 * struct rproc_ops - platform-specific device handlers
358 * @start: power on the device and boot it
359 * @stop: power off the device
360 * @kick: kick a virtqueue (virtqueue id given as a parameter)
361 * @da_to_va: optional platform hook to perform address translations
362 * @parse_fw: parse firmware to extract information (e.g. resource table)
363 * @handle_rsc: optional platform hook to handle vendor resources. Should return
364 * RSC_HANDLED if resource was handled, RSC_IGNORED if not handled and a
365 * negative value on error
366 * @load_rsc_table: load resource table from firmware image
367 * @find_loaded_rsc_table: find the loaded resouce table
368 * @load: load firmware to memory, where the remote processor
369 * expects to find it
370 * @sanity_check: sanity check the fw image
371 * @get_boot_addr: get boot address to entry point specified in firmware
372 */
373 struct rproc_ops {
374 int (*start)(struct rproc *rproc);
375 int (*stop)(struct rproc *rproc);
376 void (*kick)(struct rproc *rproc, int vqid);
377 void * (*da_to_va)(struct rproc *rproc, u64 da, int len);
378 int (*parse_fw)(struct rproc *rproc, const struct firmware *fw);
379 int (*handle_rsc)(struct rproc *rproc, u32 rsc_type, void *rsc,
380 int offset, int avail);
381 struct resource_table *(*find_loaded_rsc_table)(
382 struct rproc *rproc, const struct firmware *fw);
383 int (*load)(struct rproc *rproc, const struct firmware *fw);
384 int (*sanity_check)(struct rproc *rproc, const struct firmware *fw);
385 u32 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw);
386 };
387
388 /**
389 * enum rproc_state - remote processor states
390 * @RPROC_OFFLINE: device is powered off
391 * @RPROC_SUSPENDED: device is suspended; needs to be woken up to receive
392 * a message.
393 * @RPROC_RUNNING: device is up and running
394 * @RPROC_CRASHED: device has crashed; need to start recovery
395 * @RPROC_DELETED: device is deleted
396 * @RPROC_LAST: just keep this one at the end
397 *
398 * Please note that the values of these states are used as indices
399 * to rproc_state_string, a state-to-name lookup table,
400 * so please keep the two synchronized. @RPROC_LAST is used to check
401 * the validity of an index before the lookup table is accessed, so
402 * please update it as needed too.
403 */
404 enum rproc_state {
405 RPROC_OFFLINE = 0,
406 RPROC_SUSPENDED = 1,
407 RPROC_RUNNING = 2,
408 RPROC_CRASHED = 3,
409 RPROC_DELETED = 4,
410 RPROC_LAST = 5,
411 };
412
413 /**
414 * enum rproc_crash_type - remote processor crash types
415 * @RPROC_MMUFAULT: iommu fault
416 * @RPROC_WATCHDOG: watchdog bite
417 * @RPROC_FATAL_ERROR fatal error
418 *
419 * Each element of the enum is used as an array index. So that, the value of
420 * the elements should be always something sane.
421 *
422 * Feel free to add more types when needed.
423 */
424 enum rproc_crash_type {
425 RPROC_MMUFAULT,
426 RPROC_WATCHDOG,
427 RPROC_FATAL_ERROR,
428 };
429
430 /**
431 * struct rproc_dump_segment - segment info from ELF header
432 * @node: list node related to the rproc segment list
433 * @da: device address of the segment
434 * @size: size of the segment
435 * @priv: private data associated with the dump_segment
436 * @dump: custom dump function to fill device memory segment associated
437 * with coredump
438 */
439 struct rproc_dump_segment {
440 struct list_head node;
441
442 dma_addr_t da;
443 size_t size;
444
445 void *priv;
446 void (*dump)(struct rproc *rproc, struct rproc_dump_segment *segment,
447 void *dest);
448 loff_t offset;
449 };
450
451 /**
452 * struct rproc - represents a physical remote processor device
453 * @node: list node of this rproc object
454 * @domain: iommu domain
455 * @name: human readable name of the rproc
456 * @firmware: name of firmware file to be loaded
457 * @priv: private data which belongs to the platform-specific rproc module
458 * @ops: platform-specific start/stop rproc handlers
459 * @dev: virtual device for refcounting and common remoteproc behavior
460 * @power: refcount of users who need this rproc powered up
461 * @state: state of the device
462 * @lock: lock which protects concurrent manipulations of the rproc
463 * @dbg_dir: debugfs directory of this rproc device
464 * @traces: list of trace buffers
465 * @num_traces: number of trace buffers
466 * @carveouts: list of physically contiguous memory allocations
467 * @mappings: list of iommu mappings we initiated, needed on shutdown
468 * @bootaddr: address of first instruction to boot rproc with (optional)
469 * @rvdevs: list of remote virtio devices
470 * @subdevs: list of subdevices, to following the running state
471 * @notifyids: idr for dynamically assigning rproc-wide unique notify ids
472 * @index: index of this rproc device
473 * @crash_handler: workqueue for handling a crash
474 * @crash_cnt: crash counter
475 * @recovery_disabled: flag that state if recovery was disabled
476 * @max_notifyid: largest allocated notify id.
477 * @table_ptr: pointer to the resource table in effect
478 * @cached_table: copy of the resource table
479 * @table_sz: size of @cached_table
480 * @has_iommu: flag to indicate if remote processor is behind an MMU
481 * @auto_boot: flag to indicate if remote processor should be auto-started
482 * @dump_segments: list of segments in the firmware
483 * @nb_vdev: number of vdev currently handled by rproc
484 */
485 struct rproc {
486 struct list_head node;
487 struct iommu_domain *domain;
488 const char *name;
489 char *firmware;
490 void *priv;
491 struct rproc_ops *ops;
492 struct device dev;
493 atomic_t power;
494 unsigned int state;
495 struct mutex lock;
496 struct dentry *dbg_dir;
497 struct list_head traces;
498 int num_traces;
499 struct list_head carveouts;
500 struct list_head mappings;
501 u32 bootaddr;
502 struct list_head rvdevs;
503 struct list_head subdevs;
504 struct idr notifyids;
505 int index;
506 struct work_struct crash_handler;
507 unsigned int crash_cnt;
508 bool recovery_disabled;
509 int max_notifyid;
510 struct resource_table *table_ptr;
511 struct resource_table *cached_table;
512 size_t table_sz;
513 bool has_iommu;
514 bool auto_boot;
515 struct list_head dump_segments;
516 int nb_vdev;
517 };
518
519 /**
520 * struct rproc_subdev - subdevice tied to a remoteproc
521 * @node: list node related to the rproc subdevs list
522 * @prepare: prepare function, called before the rproc is started
523 * @start: start function, called after the rproc has been started
524 * @stop: stop function, called before the rproc is stopped; the @crashed
525 * parameter indicates if this originates from a recovery
526 * @unprepare: unprepare function, called after the rproc has been stopped
527 */
528 struct rproc_subdev {
529 struct list_head node;
530
531 int (*prepare)(struct rproc_subdev *subdev);
532 int (*start)(struct rproc_subdev *subdev);
533 void (*stop)(struct rproc_subdev *subdev, bool crashed);
534 void (*unprepare)(struct rproc_subdev *subdev);
535 };
536
537 /* we currently support only two vrings per rvdev */
538
539 #define RVDEV_NUM_VRINGS 2
540
541 /**
542 * struct rproc_vring - remoteproc vring state
543 * @va: virtual address
544 * @len: length, in bytes
545 * @da: device address
546 * @align: vring alignment
547 * @notifyid: rproc-specific unique vring index
548 * @rvdev: remote vdev
549 * @vq: the virtqueue of this vring
550 */
551 struct rproc_vring {
552 void *va;
553 int len;
554 u32 da;
555 u32 align;
556 int notifyid;
557 struct rproc_vdev *rvdev;
558 struct virtqueue *vq;
559 };
560
561 /**
562 * struct rproc_vdev - remoteproc state for a supported virtio device
563 * @refcount: reference counter for the vdev and vring allocations
564 * @subdev: handle for registering the vdev as a rproc subdevice
565 * @id: virtio device id (as in virtio_ids.h)
566 * @node: list node
567 * @rproc: the rproc handle
568 * @vdev: the virio device
569 * @vring: the vrings for this vdev
570 * @rsc_offset: offset of the vdev's resource entry
571 * @index: vdev position versus other vdev declared in resource table
572 */
573 struct rproc_vdev {
574 struct kref refcount;
575
576 struct rproc_subdev subdev;
577 struct device dev;
578
579 unsigned int id;
580 struct list_head node;
581 struct rproc *rproc;
582 struct rproc_vring vring[RVDEV_NUM_VRINGS];
583 u32 rsc_offset;
584 u32 index;
585 };
586
587 struct rproc *rproc_get_by_phandle(phandle phandle);
588 struct rproc *rproc_get_by_child(struct device *dev);
589
590 struct rproc *rproc_alloc(struct device *dev, const char *name,
591 const struct rproc_ops *ops,
592 const char *firmware, int len);
593 void rproc_put(struct rproc *rproc);
594 int rproc_add(struct rproc *rproc);
595 int rproc_del(struct rproc *rproc);
596 void rproc_free(struct rproc *rproc);
597
598 void rproc_add_carveout(struct rproc *rproc, struct rproc_mem_entry *mem);
599
600 struct rproc_mem_entry *
601 rproc_mem_entry_init(struct device *dev,
602 void *va, dma_addr_t dma, int len, u32 da,
603 int (*alloc)(struct rproc *, struct rproc_mem_entry *),
604 int (*release)(struct rproc *, struct rproc_mem_entry *),
605 const char *name, ...);
606
607 struct rproc_mem_entry *
608 rproc_of_resm_mem_entry_init(struct device *dev, u32 of_resm_idx, int len,
609 u32 da, const char *name, ...);
610
611 int rproc_boot(struct rproc *rproc);
612 void rproc_shutdown(struct rproc *rproc);
613 void rproc_report_crash(struct rproc *rproc, enum rproc_crash_type type);
614 int rproc_coredump_add_segment(struct rproc *rproc, dma_addr_t da, size_t size);
615 int rproc_coredump_add_custom_segment(struct rproc *rproc,
616 dma_addr_t da, size_t size,
617 void (*dumpfn)(struct rproc *rproc,
618 struct rproc_dump_segment *segment,
619 void *dest),
620 void *priv);
621
622 static inline struct rproc_vdev *vdev_to_rvdev(struct virtio_device *vdev)
623 {
624 return container_of(vdev->dev.parent, struct rproc_vdev, dev);
625 }
626
627 static inline struct rproc *vdev_to_rproc(struct virtio_device *vdev)
628 {
629 struct rproc_vdev *rvdev = vdev_to_rvdev(vdev);
630
631 return rvdev->rproc;
632 }
633
634 void rproc_add_subdev(struct rproc *rproc, struct rproc_subdev *subdev);
635
636 void rproc_remove_subdev(struct rproc *rproc, struct rproc_subdev *subdev);
637
638 #endif /* REMOTEPROC_H */